internal static void DrawAxisLine(VertexHelper vh, Axis axis, AxisTheme theme, Orient orient,
                                          float startX, float startY, float axisLength)
        {
            var inverse = axis.IsValue() && axis.inverse;
            var offset  = AxisHelper.GetAxisLineArrowOffset(axis);

            var lineWidth = axis.axisLine.GetWidth(theme.lineWidth);
            var lineType  = axis.axisLine.GetType(theme.lineType);
            var lineColor = axis.axisLine.GetColor(theme.lineColor);

            if (orient == Orient.Horizonal)
            {
                var left  = new Vector3(startX - lineWidth - (inverse ? offset : 0), startY);
                var right = new Vector3(startX + axisLength + lineWidth + (!inverse ? offset : 0), startY);
                ChartDrawer.DrawLineStyle(vh, lineType, lineWidth, left, right, lineColor);
            }
            else
            {
                var bottom = new Vector3(startX, startY - lineWidth - (inverse ? offset : 0));
                var top    = new Vector3(startX, startY + axisLength + lineWidth + (!inverse ? offset : 0));
                ChartDrawer.DrawLineStyle(vh, lineType, lineWidth, bottom, top, lineColor);
            }
        }
        protected void DrawAxisSplit(VertexHelper vh, AxisTheme theme, DataZoom dataZoom,
                                     Orient orient, float startX, float startY, float axisLength, float splitLength, Axis relativedAxis = null)
        {
            Axis axis      = component;
            var  lineColor = axis.splitLine.GetColor(theme.splitLineColor);
            var  lineWidth = axis.splitLine.GetWidth(theme.lineWidth);
            var  lineType  = axis.splitLine.GetType(theme.splitLineType);

            var size = AxisHelper.GetScaleNumber(axis, axisLength, dataZoom);

            if (axis.IsTime())
            {
                size += 1;
                if (!ChartHelper.IsEquals(axis.GetLastLabelValue(), axis.context.maxValue))
                {
                    size += 1;
                }
            }

            var current = orient == Orient.Horizonal ?
                          startX :
                          startY;

            for (int i = 0; i < size; i++)
            {
                var scaleWidth = AxisHelper.GetScaleWidth(axis, axisLength, axis.IsTime() ? i : i + 1, dataZoom);

                if (axis.boundaryGap && axis.axisTick.alignWithLabel)
                {
                    current -= scaleWidth / 2;
                }

                if (axis.splitArea.show && i <= size - 1)
                {
                    if (orient == Orient.Horizonal)
                    {
                        UGL.DrawQuadrilateral(vh,
                                              new Vector2(current, startY),
                                              new Vector2(current, startY + splitLength),
                                              new Vector2(current + scaleWidth, startY + splitLength),
                                              new Vector2(current + scaleWidth, startY),
                                              axis.splitArea.GetColor(i, theme));
                    }
                    else
                    {
                        UGL.DrawQuadrilateral(vh,
                                              new Vector2(startX, current),
                                              new Vector2(startX + splitLength, current),
                                              new Vector2(startX + splitLength, current + scaleWidth),
                                              new Vector2(startX, current + scaleWidth),
                                              axis.splitArea.GetColor(i, theme));
                    }
                }
                if (axis.splitLine.show)
                {
                    if (axis.splitLine.NeedShow(i))
                    {
                        if (orient == Orient.Horizonal)
                        {
                            if (relativedAxis == null || !MathUtil.Approximately(current, GetAxisLineXOrY()))
                            {
                                ChartDrawer.DrawLineStyle(vh,
                                                          lineType,
                                                          lineWidth,
                                                          new Vector3(current, startY),
                                                          new Vector3(current, startY + splitLength),
                                                          lineColor);
                            }
                        }
                        else
                        {
                            if (relativedAxis == null || !MathUtil.Approximately(current, GetAxisLineXOrY()))
                            {
                                ChartDrawer.DrawLineStyle(vh,
                                                          lineType,
                                                          lineWidth,
                                                          new Vector3(startX, current),
                                                          new Vector3(startX + splitLength, current),
                                                          lineColor);
                            }
                        }
                    }
                }
                current += scaleWidth;
            }
        }
        internal static void DrawAxisTick(VertexHelper vh, Axis axis, AxisTheme theme, DataZoom dataZoom,
                                          Orient orient, float startX, float startY, float axisLength)
        {
            var lineWidth  = axis.axisLine.GetWidth(theme.lineWidth);
            var tickLength = axis.axisTick.GetLength(theme.tickLength);

            if (AxisHelper.NeedShowSplit(axis))
            {
                var size = AxisHelper.GetScaleNumber(axis, axisLength, dataZoom);

                var current = orient == Orient.Horizonal ?
                              startX :
                              startY;

                for (int i = 0; i < size; i++)
                {
                    var scaleWidth = AxisHelper.GetScaleWidth(axis, axisLength, i + 1, dataZoom);
                    if (i == 0 && (!axis.axisTick.showStartTick || axis.axisTick.alignWithLabel))
                    {
                        current += scaleWidth;
                        continue;
                    }
                    if (i == size - 1 && !axis.axisTick.showEndTick)
                    {
                        current += scaleWidth;
                        continue;
                    }
                    if (axis.axisTick.show)
                    {
                        if (orient == Orient.Horizonal)
                        {
                            float pX = axis.IsTime() ?
                                       (startX + axis.GetDistance(axis.GetLabelValue(i), axisLength)) :
                                       current;

                            if (axis.boundaryGap && axis.axisTick.alignWithLabel)
                            {
                                pX -= scaleWidth / 2;
                            }

                            var sY = 0f;
                            var eY = 0f;
                            if ((axis.axisTick.inside && axis.IsBottom()) ||
                                (!axis.axisTick.inside && axis.IsTop()))
                            {
                                sY = startY + lineWidth;
                                eY = sY + tickLength;
                            }
                            else
                            {
                                sY = startY - lineWidth;
                                eY = sY - tickLength;
                            }

                            UGL.DrawLine(vh, new Vector3(pX, sY), new Vector3(pX, eY),
                                         axis.axisTick.GetWidth(theme.tickWidth),
                                         axis.axisTick.GetColor(theme.tickColor));
                        }
                        else
                        {
                            float pY = axis.IsTime() ?
                                       (startY + axis.GetDistance(axis.GetLabelValue(i), axisLength)) :
                                       current;

                            if (axis.boundaryGap && axis.axisTick.alignWithLabel)
                            {
                                pY -= scaleWidth / 2;
                            }

                            var sX = 0f;
                            var eX = 0f;
                            if ((axis.axisTick.inside && axis.IsLeft()) ||
                                (!axis.axisTick.inside && axis.IsRight()))
                            {
                                sX = startX + lineWidth;
                                eX = sX + tickLength;
                            }
                            else
                            {
                                sX = startX - lineWidth;
                                eX = sX - tickLength;
                            }

                            UGL.DrawLine(vh, new Vector3(sX, pY), new Vector3(eX, pY),
                                         axis.axisTick.GetWidth(theme.tickWidth),
                                         axis.axisTick.GetColor(theme.tickColor));
                        }
                    }
                    current += scaleWidth;
                }
            }
            if (axis.show && axis.axisLine.show && axis.axisLine.showArrow)
            {
                var lineY     = startY + axis.offset;
                var inverse   = axis.IsValue() && axis.inverse;
                var axisArrow = axis.axisLine.arrow;
                if (orient == Orient.Horizonal)
                {
                    if (inverse)
                    {
                        var startPos = new Vector3(startX + axisLength, lineY);
                        var arrowPos = new Vector3(startX, lineY);
                        UGL.DrawArrow(vh, startPos, arrowPos, axisArrow.width, axisArrow.height,
                                      axisArrow.offset, axisArrow.dent,
                                      axisArrow.GetColor(axis.axisLine.GetColor(theme.lineColor)));
                    }
                    else
                    {
                        var arrowPosX = startX + axisLength + lineWidth;
                        var startPos  = new Vector3(startX, lineY);
                        var arrowPos  = new Vector3(arrowPosX, lineY);
                        UGL.DrawArrow(vh, startPos, arrowPos, axisArrow.width, axisArrow.height,
                                      axisArrow.offset, axisArrow.dent,
                                      axisArrow.GetColor(axis.axisLine.GetColor(theme.lineColor)));
                    }
                }
                else
                {
                    if (inverse)
                    {
                        var startPos = new Vector3(startX, startY + axisLength);
                        var arrowPos = new Vector3(startX, startY);
                        UGL.DrawArrow(vh, startPos, arrowPos, axisArrow.width, axisArrow.height,
                                      axisArrow.offset, axisArrow.dent,
                                      axisArrow.GetColor(axis.axisLine.GetColor(theme.lineColor)));
                    }
                    else
                    {
                        var startPos = new Vector3(startX, startY);
                        var arrowPos = new Vector3(startX, startY + axisLength + lineWidth);
                        UGL.DrawArrow(vh, startPos, arrowPos, axisArrow.width, axisArrow.height,
                                      axisArrow.offset, axisArrow.dent,
                                      axisArrow.GetColor(axis.axisLine.GetColor(theme.lineColor)));
                    }
                }
            }
        }
        internal static Vector3 GetLabelPosition(int i, Orient orient, Axis axis, Axis relativedAxis, AxisTheme theme,
                                                 float scaleWid, float axisStartX, float axisStartY, float axisLength, float relativedLength)
        {
            var inside   = axis.axisLabel.inside;
            var fontSize = axis.axisLabel.textStyle.GetFontSize(theme);
            var current  = axis.offset;

            if (axis.IsTime() || axis.IsValue())
            {
                scaleWid = axis.context.minMaxRange != 0 ?
                           axis.GetDistance(axis.GetLabelValue(i), axisLength) :
                           0;
            }

            if (orient == Orient.Horizonal)
            {
                if (axis.axisLabel.onZero && relativedAxis != null)
                {
                    axisStartY += relativedAxis.context.offset;
                }

                if (axis.IsTop())
                {
                    axisStartY += relativedLength;
                }

                if ((inside && axis.IsBottom()) || (!inside && axis.IsTop()))
                {
                    current += axisStartY + axis.axisLabel.distance + fontSize / 2;
                }
                else
                {
                    current += axisStartY - axis.axisLabel.distance - fontSize / 2;
                }

                return(new Vector3(axisStartX + scaleWid, current) + axis.axisLabel.offset);
            }
            else
            {
                if (axis.axisLabel.onZero && relativedAxis != null)
                {
                    axisStartX += relativedAxis.context.offset;
                }

                if (axis.IsRight())
                {
                    axisStartX += relativedLength;
                }

                if ((inside && axis.IsLeft()) || (!inside && axis.IsRight()))
                {
                    current += axisStartX + axis.axisLabel.distance;
                }
                else
                {
                    current += axisStartX - axis.axisLabel.distance;
                }

                return(new Vector3(current, axisStartY + scaleWid) + axis.axisLabel.offset);
            }
        }